催化学报

催化学报 ›› 2009, Vol. 30 ›› Issue (11): 1125-1130.

• 研究论文 • 上一篇    下一篇

沉淀方法对Ru/CeO2氨合成催化剂催化性能的影响

罗小军, 王榕, 林建新, 魏可镁   

  1. 福州大学化肥催化剂国家工程研究中心, 福建福州 350002
  • 收稿日期:2009-11-25 出版日期:2009-11-25 发布日期:2013-07-17

Effect of Precipitation Methods on Catalytic Activity of Ru/CeO2 Catalyst for Ammonia Synthesis

LUO Xiaojun, WANG Rong*, LIN Jianxin, WEI Kemei   

  1. National Research Center of Chemical Fertilizer Catalysts, Fuzhou University, Fuzhou 350002, Fujian, China
  • Received:2009-11-25 Online:2009-11-25 Published:2013-07-17

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摘要： 采用沉淀法制备了 Ru/CeO2 氨合成催化剂, 并运用 N2 物理吸附、X 射线衍射、X 射线荧光光谱、CO 吸附和 H2 程序升温还原等技术对其进行了表征, 考察了沉淀时反应液的并流、反加、正加以及沉积-沉淀对所制备的 Ru/CeO2 催化剂氨合成性能的影响. 结果表明, 不同制备方法所得到的催化剂, 其氯残留量和载体的还原性能都存在明显的差别, 最终影响了催化剂的氨合成活性, 其中采用正加法制备的催化剂上氯残留量少, 载体易还原, 因而催化活性最高, 在 10 MPa, 10 000 h?1, 450 oC 反应时, NH3 浓度达到 11.9%.

关键词: 沉淀方法, 氨合成, 二氧化铈, 钌, 共沉淀, 沉积-沉淀

Abstract: The Ru/CeO2 catalyst was prepared by precipitation methods, including normal precipitation, reverse precipitation, parallel flow precipitation, and deposition-precipitation. The obtained catalysts were characterized by N2 adsorption-desorption, X-ray diffraction, H2 temperature-programmed reduction, CO chemisorption, and X-ray fluorescence spectroscopy. The results showed that the ammonia synthesis activity of the Ru/CeO2 catalyst prepared by normal precipitation was 11.9% at 10 MPa, 10000 h-1,?and 450 oC, which was higher than those obtained by other methods. The residual chloride content in this catalyst was much lower and its cerium was easier to be reduced. Thus the activity of the catalyst prepared using normal precipitation was high.

Key words: precipitation method, ammonia synthesis, cerium dioxide, ruthenium, co-precipitation, deposition-precipitation